One of the more difficult and time consuming tasks in a printing operation is the need to periodically clean the various printing press rollers and cylinders, such as the blanket cylinder, impression cylinder, plate cylinder and, in particular, the ink rollers (collectively referred to as an "ink roller train") of ink and other debris. These cleaning operations are sometimes referred to by those skilled in the art as "washings" or "washup" operations. Such washup operations are needed to remove extraneous paper dust, debris, and other contaminants from the ink roller train to improve the quality of the printed product. An ink roller train washup operation is also required when ink color changes are implemented by the press operator.
Ink roller washings are tedious operations, often requiring significant (and sometimes dangerous) manual intervention on the part of the press operator. The print operator will usually "squirt" or otherwise apply a cleaning solvent directly onto the print cylinders and ink roller train. The solvent loosens the ink and other debris from the cylinders and ink rollers, which is then scraped off or otherwise removed from the printing press. The scraping operation is a messy and time consuming task, and in the past has involved manually wiping the surface of the cylinders and rollers so that the solvent, along with the ink and other solid debris, can be collected in a trough or pan, or alternatively, captured by a rag or some other absorbent material.
As an alternative to manually cleaning the printing press, the washup operation may also be performed by devices designed to engage the cylinders or ink rollers and scrape off the ink or other debris. Such devices include, for example, inflatable bladders which fill with air or other gases to lightly touch the surface of the cylinder or roller and remove debris. Devices using a wiping blade have also been used to scrape debris from cylinders and inking rollers. However, it is frequent that the blade is inadequately cleaned following a washup operation. The result is that the geometry of the blade tip is altered with subsequent washings, lowering both the effectiveness of the blade in cleaning the press rollers, and lessening the effective life expectancy of the blade.
FIGS. 1A and 1B illustrate in perspective a prior embodiment of a press washer system for inking rollers. One example of such a prior art system is the Model 430 "Automatic Press Ink Roller Washer" manufactured by Baldwin Graphic Products of Stamford, Connecticut. As shown in FIG. 1, a typical prior art press washer system 10 includes a blade assembly 24 pivotally mounted onto the printing press 14 with a blade unit 12 serving to clean the inking roller train 16. The blade assembly 24 is pivoted into engagement with the roller train 16 via a piston actuation means 52 controlled by a solenoid 54. The system 10 also includes, for example, one or more spray bars 20 mounted at or near the top end of ink roller train 16. The spray bars 20 supply cleaning solvent or fluid onto the ink roller train 16. Excess solvent is collected in a spray bar drip pan 22 mounted beneath the spray bars 20, and returned to a collection system (not shown). The solvent flows through the individual rollers forming the inking train 16. Through pressing action between the rollers, ink and debris is removed therefrom, flowing to the lower portion of the ink roller train 16.
As shown, the system 10 has the blade assembly 24 pivotally mounted to the press frame at a lower portion of the inking roller train 16. The blade assembly 24 removes ink, debris, or other contaminants from the ink roller train 16 during a washings operation, and accumulates such debris in a drip pan or receptacle trough 18. Upon actuation of the blade assembly 24, the blade unit 12 engages a roller 15 of the inking train 16 to remove the ink and solvent that has been released from the inking train 16. The ink and solvent is then collected in the press washer trough 18 for final disposal. However, both the blade unit and trough are unprotected from being stained or soiled by the ink and solvent; are subject to the deleterious effects, such as blade wear, as previously noted; and thus require significant manual operator intervention during and following a washup operation.
A typical press washer system may also include a controller 40 (shown in FIG. 2) for controlling the operation of the press washer system 10. In some cases, the controller 40 allows a press operator to simultaneously control a plurality of separate press washer systems 10. The controller 40 usually includes commercially available software, electronic components and internal circuitry known to those skilled in the art, for controlling the washer systems 10. As illustrated in FIG. 2, the system controller 40 is operatively connected to an operator control panel 42 having a plurality of keypad inputs for controlling critical features of the systems 10. For example, through use of the keypads, the press operator may enter system parameters and information, including spray wash time, press cleaning time, and other variables that dictate operation of the press washer systems 10.
Typically, input connections 45 to the individual washer system 10 are linked through a fluid/air box 46, to control the supply of cleaning solvent and pressurized air from central sources designed to supply a plurality of press washer systems 10. As illustrated in FIGS. 2 and 3, the individual fluid/air boxes 46 include one or more solvent valves 48 and an air valve 50 to regulate the supply of solvent fluids and pressurized air to each individual washer system 10. The solvent valves 48 are operatively connected to the individual spray bars 20, while the air valve 50 is operatively connected to a piston actuation means 52 (as shown in FIG. 1B) for controlling actuation of the blade assembly 24. These valves 48, 50 are individually controlled by solenoids 54 whose operation is controlled by the system controller 40. Thus, the press operator can control opening and/or closing of the valves 48, 50 by operating the appropriate solenoid 54 through information input into the control panel 42. Entry of this information sends signals to the system controller 40, which controls actuation of the solenoids 54 in the individual air/fluid boxes 46, and regulates the amount and duration of solvent emissions through the spray bars 20 and air emission into the actuation means 50 for controlling actuation of the blade assembly 24 against the roller 15.
The final aspect of the washup operation entails the collection and disposal of the fluid and solid wastes removed from the inking roller train 16. An inherent disadvantage with systems such as those described above comes from the liquid and solid debris that is collected in a tray or pan. In these systems, the pan often forms a permanent fixture of the ink roller washings unit, and has to be painstakingly removed from the printing press in order for the pressman to dispose of the liquid and solid debris collected therein. Another disadvantage with systems such as these described above is that none of the system components are protected from staining by ink, solvent or debris. Upon completion of the washings operation, it is necessary to manually clean the collecting pan, the bladder or blade, and other components of the washings assembly prior to renewing printing operations. Such tasks are tedious, time consuming and messy, and result in prolonged periods of press downtime while the operator cleans the stained components. As a result of these inconveniences it is often the case that washups are neglected by the operator, causing undue wear to the components and lessening their life expectancy.
One approach to addressing these problems is disclosed, for example, in PCT Application JP90/00191, directed to a "Method and Device for Cleaning an Ink Roller Train for use in Printing Machines." Referring to FIG. 8 of the reference, a special cleaning cloth, chemically treated with an oil coagulant, is used in conjunction with a doctor blade to scrape softened ink from an ink roller and onto the cloth so that it is absorbed. The device requires special heater apparatus to heat the cleaning cloth so as to melt the oil coagulant in order that it mix with the ink. The cloth is then allowed to air-cool, so that the ink is gelatinized within the cleaning cloth for disposal. The approach taught by this reference entails use of special machines, including heater apparatus disposed on the underside of the ink collection pan, and is not readily amenable to retrofit applications to existing printing presses. Moreover, this prior device is not directed to preventing or reducing the soiling of the system components utilized during the washup operation, instead employing the special cleaning cloth as a complicated means unto itself for collecting waste ink and solvent from the system. The operator would still need to clean the system components after washup operations.
There exists a need, therefore, for a washup device for the various cylinders and rollers and inking system rollers used in printing presses, and in particular, for an improvement to the blade assembly, which facilitates the automation of washings operations; which is easily retrofitted into existing printing presses without the need for complicated additions; which keeps the blade clean to prolong its life and reduce wear, so that the blade can maintain its geometry to effectively scrape the ink rollers during washup; and which simplifies disposal of the collected solid and liquid wastes while eliminating the time and effort necessary to clean the washings components between washings operations.
It is therefore an object of the present invention to provide an automatic press washer system having an improved blade assembly and a sheathing system for the washup components for use in cleaning the various press rollers and the ink roller train of a printing press.
It is an additional object of the present invention to provide on automatic press washer system having an improved blade assembly with a sheathing system for cleaning the cylinders and ink roller train of a printing press, which reduces the time and effort required to clean system components between washings operations.
It is a further object of the present invention to provide an automatic press washer system having an improved blade assembly for cleaning the cylinders and ink roller train of a printing press, which facilitates the removal and disposal of used solvent, ink, and solid debris collected from the various press rollers and the ink roller train following a washings operation.
It is yet an additional object of the present invention to provide an automatic press washer system having an improved blade assembly for cleaning the cylinders and ink roller train of a printing press which is easily retrofitted into existing printing press units without the need for extraneous components.
It is still an additional object of the present invention to provide an automatic press washer system having an improved blade assembly for cleaning the cylinders and ink roller train of a printing press, which protects the individual components from being soiled, stained, or covered by ink, solvent or debris during a washings operation.
The foregoing specific objects and advantages of the invention are illustrative of those which can be achieved by the present invention and are not intended to be exhaustive or limiting of the possible advantages of the invention, which will be apparent from the description herein or can be learned from practicing the invention, both as embodied herein or as modified in view of any variations which may be apparent to those skilled in the art. Accordingly, the present invention resides in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.